In a display device in the prior art, a pixel usually comprises three sub pixels of different colors, including red (R), green (G) and blue (B). The color and brightness presented by the pixel can be controlled by adjusting the respective gray scales of the three sub pixels. Thus, the above display device can also be called a RGB display device.
However, each of the sub pixels of the RGB display device can filter the white light emitted by the backlight thereof, rendering the transmittance of the light emitted by the backlight of the existing RGB display device relatively low. In order to ensure the brightness of the RGB display device, it is necessary to improve the luminous efficiency of the backlight, which causes relatively large power consumption and high cost to use of the RGB display device.
In order to decrease the power consumption of the display device, a RGBW display device emerges. The RGBW display device comprises sub pixels of four colors, namely red (R), green (G), blue (B), and white (W). Because a white pixel would not filter the light, the transmittance of the light emitted by the backlight of the display device can be improved, thereby the power consumption of the display device can be reduced.
However, it is found that in the prior art, each sub pixel needs to be driven by a separate data line. A data line is usually made by non-transparent conductive metal, which would negatively influence the light transmittance of the display device.